It has been known that protein misfolding causes normal proteins to lose their function and abnormal proteins to be accumulated in cells and produce toxicity and thus causes various diseases such as Alzheimer's disease, Parkinson's disease, Huntington's chorea, Lou Gehrig's disease, cancer, cystic fibrosis, and type II diabetes. That is, malfunction of proteostasis causes protein misfolding and its intracellular abnormal accumulation.
All the causes of neurodegenerative diseases have not yet been found, but it has been well known that aggregation of neuronal proteins is a main cause. Fibrillated proteins are gradually transmitted to adjacent neurons and finally necrose all the neurons in a specific part of the brain, so that the specific part cannot perform its functions. As for Parkinson's disease, the disease progresses while neurons that produce a neurotransmitter called dopamine are gradually necrosed. Sinemet is now the most common drug prescribed to Parkinson's disease patients, and Sinemet and other Parkinson's disease drugs do not function to fundamentally treat or delay the disease but supply Levodopa (L-DOPA) which is converted into dopamine in neurons to temporally reduce the symptoms. In the end, as the disease continues to progress, the effect of the drugs decreases, which causes death.
As one of anti-amyloid compounds researched relating to protein misfolding, Congo Red has an effect of inhibiting fibril formation caused by protein misfolding but is highly toxic to the body and cannot function to inhibit transition of misfolded proteins and thus delay the progress of a disease. Further, a conventional drug is formulated into a specific shape with a uniform size and thus does not have any particular advantage in the treatment of a disease in terms of entropy.
Accordingly, a lot of studies have been carried out to treat protein misfolding (Korean Patent Laid-open Publication No. 10-2009-0019790), but there has been no great achievement about a drug which is not toxic to the body but has an excellent inhibitory activity.